Means for heating and cooling



Dec. 26, 1944. F. R. BICHOWSKY MEANS FOR HEATING AND COOLING Filed May 29, 1940 FIG. I.

INVENTOR Patented Ded zc, 1944.

. MEANS FOR HEATING AND COOLING Francis R. Bichowsky, WashingtomD. C.

' Application May 29, 1940, Serial No. 337,857.,

- 20 Claims; (Cl. 62I19) This invention relates to improved apparatus for heating and cooling fluids. More specifically the invention is concerned with an improved apparatus of the vacuum absorption type for heating and cooling air. Refrigerants commonly employed arewater, methyl alcohol, or the like and frequently used absorbents are solutions of 11th-.

bromide, zinc chloride, and

means for separating the absorbent and primary refrigerant after admixture thereof. A primary object 'of the invention is to provide an apparatus which can be employed either for heating or for cooling the air in buildings.

To the accomplishment of the foregoing ancL related ends, the invention, then consists of the means hereinafter fully described and particu-,'

larly pointed out in the claims,- the annexeddrawing and the following description setting forth in detail certain means for carrying out the invention, such disclosed means illustrating,-however, but one of various ways in which the principle of the invention may be used.

In said annexed drawing: Figure 1 is a crosssectional elevation of a vacuum absorption apparatus illustrating the principle of the present 35 invention. Figure 2 is a plan viewof, the heat exchanger I! in Figure 1 taken on the line 2- -2. Fig. 3 is an enlarged perspective of the tube 4 shown in Fig. 1. 1

communication with this coil 33 is a pipe 28 which distributes vaporized secondary refrigerant entering through a header tube I within the finned pipe 4. A footing tube 6 collects secondary refrigerant condensing in the pipe 4 and conveys it out of the evaporator section by. the footing tube 8 and the pipe 32.. The helical fins 5 on the pipe 4 (in Fig. 3) are so spacedthat liquid primary refrigerant distributed to the fins 5 by the distributing means 3 is constrained by capillarity to follow the helix. A shield 34 is provided in the evaporator to restrict evaporation and prevent flashing of said refrigerant into fine spray Any small portion of the refrigerant which escapes evaporation flows by the drain pipe 35 into an absorber section 9. The absorber 9 is below and in open communication with the evaporator 30. An opening 36 between the two chambers is provided so that vapor produced in the evaporator 30 may flow into the absorber 9 or from the absorber 9 to the evaporator 30. -A- spiral channel 31 is formed for distributing the absorbent in the absorber 9 in a thin film so that a large surface of; said absorbent is provided for the absorption of vapor. The spiral channel 31 contains 'a coil in in thermal communication therewith so that when a cooling liquid flows through the coil l0, entering by means of the In Figure 1, an hermetically sealed vessel 21 40 is provided in the form of a closed cylinder. This vessel is separated intosix compartments or zones by means of suitable partitions. The upper compartment 30 is hereinafter called the the top thereof. Becauseof the vacuummbtaining in the chamber 30, refrigerant entering through the'pipe 2 evaporates in'tHe evaporator 30 and is thereby cooled; Heatls thereby 'abstracted from a secondary refrigerant circulat ing in the finned pipe liwhich may be dichlordifluormethane or the like. The so-cooled secondary refrigerant is then circulated through a coil 33 over whichv air to be cooled is passed. In 55 but, in the illustrated example, is formed by conheader tube 8 and'leaving by the footing tube -30 52, the absorbent flows in the absorber 9 downthe spiral channel 31 and the heat of absorption produced is carried away by the water in Elie cooling coils Ill.

' The'cooling liquid leaving the pipe 52 may go to waste or preferably, as shown in my co-pending application Serial No. 286,989, filed July 28, 1939, now issued as U. S. Patent 2,289,924, October 13, 1942, may flow to the coil 44, by the pipe 58, and to was'teby pipe 58. There is provided a passage! connecting the absorber chamber 8 with the space 3| left betweenthe shell of the evaporator 30 and the outer vessel 21 which serves as a deadend space in'which any small amount of inert gas is forced by the flow of water vapor f Evaporator. The evaporator 30 is provided with from the evaporator to the absorber 8. A par.-

. a means 3 far introducing liquid refrigerant near tition Ilsparat'es the chambers 30 and 9 from '50 lower sections of the vessel 21. The partition l2 forms the bottom of the absorber and the weakened absorbent'is transported therefrom by the pipe 38 to the heat exchanger II.

The lieatexchanger I1 is of any construction necting several pipes IE to a header tube 38 and winding said pipes, together with a spacing sheet l8, so as to form -a spiral coil of pipes in which the pipes I6 are spaced by the sheet l8.

The spiral pipes l5 and sheet I8 are capped top and bottom by the plates 4|, 42. In this way two passages are formed, one within the multiple pipe l6 and the other comprising the spaces between the multiple pipe IS, the spiral sheet l8 and the top and bottom sheets 4|, 42.

Liquor entering the exchanger by the header tube 38 thus flows by the multiple pipe I6 out through the header tube 50 which leads downward into a regenerator 49. The regenerator 49 is placed at the bottom of the vessel 21 so as to be readily heated by a heating device 5|. Provided on the inside of the regenerator section 49 and above the boiling liquid is a shield 23 pierced by a tube 24 which leads upward and through the center of the spiral exchanger l1 into a pipe 40 protruding into the circular chamber l3 which is a device for separating intermingled liquid and vapor. Vapor produced by the boiling absorbent in the regenerator 49 enters the tube 24 carrying with it a portion of the liquid absorbent in accordance with the vapor-lift principle. The mixed vapor and liquid absorbent are directed by an extension 40 of the pipe 24 in a tangential manner against the inside of the vapor separator l3, thus separating the vapor and the intermingled liquid, the liquid flowing by the pipe l5 to the passage in the heat exchanger l1 formed by the multiple pipe l8 and the spiral sheet l8. The hot absorbent then flows following the channel formed by the multiple pipe l6 and the spiral sheet l8 counter-current to the absorbent in the multiple pipe i6. Heat is, therefore, exchanged between the hot absorbent and the absorbent entering by pipe "so that the absorbent leaving by the pipe ii is oooledwhile the absorbent entering by the header tube 38 is heated. The cooled absorbent then flows by the pipe H upward into theabsorber 9 being forced to flow upward by the difference in pressure between that in the vapor separator l3 and that in the absorber 9. The vapor separated in the vapor separator l3 flows by the pipe l4 inclosing the pipe 24 into a condenser section 43. The condenser section 43 is provided with cooling coils 44 upon which the vaporized refrigerant condenses and collects on the fioor .45 which is'insulated by the space 46, from the regenerator 49. Condensed liquid collecting on the floor 45 flows through the pipe l9 to the pipe 20 which forms a leg capable of, in part, supporting the vessel 21. Inside of the pipe 29 a pipe 2i is provided which connects with the pipe 2 and serves to convey refrigerant from the condenser 43 to the evaporator 30. The vertical distance between the condenser 43 and the evaporator 30, and between the heat exchanger l1 and the absorber 9 and'the levels of liquid in the regenerator 49, the vapor separator 13, the condenser 43, the absorber 9, and the evaporator a pipe 41, the pipe 41 being connected-by the pipe 48 to the regenerator 49. The pipe 41 with its inner pipe 39 forms a second leg for the support of the unit and functions as follows: In the event of an unusual rate of boiling, the liquid in the vapor separator I3 may rise to such a point that it tends to overflow with the vapor down the pipe I4. To prevent this; the pipe 39 conveys excess liquor from the vapor separator i3 back to the regenerator 49. A pipe 26 is provided communicating at a level above the normal liquid level in the condenser 43 and leading downward within a pipe which latter serves as' a third leg forthe apparatus. This leg is placed out of the plane of the drawing but is shown in the plane for purposes of simplification. The pipe 25 connects by the pipe 22 to the regenerator 49. The pipes 26, 25, 22 allow any excess liquid collecting in the condenser 43 to flow therefrom back to the regenerator 49.

While the mode of operation of the specific apparatus illustrated has been described, my method broadly comprises recirculating a secondary refrigerant in heat exchange relation with fluids to be cooled or heated and in heat exchange relation with a primary refrigerant; passing said primary refrigerant from heat exchange relation with said secondary refrigerant into absorbing medium; circulating a portion of the so-formed mixture of absorbing medium and primary refrigerant through a heated zone, thence into a vapor-liquid separating zone and returning the separated liquid to said absorption zone in heat exchange relation with the mixture of primary refrigerant and absorbing medium leaving said absorption zone; passing the vapor leaving said vapor-liquid separator zone through a condenser and returning the resulting material to heat exchange relation with said secondary refrigerant; and controlling the heat supplied to said secondary refrigerant by controlling the amount of heat removed from said condenser and from said absorber.

positive heat is supplied, the fluid is heated, and if negative heat is supplied, the fluid is cooled. In order to utilize this invention for heating it is only necessary to decrease the flow of cooling water passing through the cooling coils by means of valves shown in my co-pending application Ser. No. 286,989, filed July 28, 1939, now issued as U. S. Patent 2,289,924 of October 13, 1942. When the temperature of the absorbent in the absorber is raised by the heat of absorption to the point where it exceeds the temperature at which the absorbtion of water vapor can proceed, water vapor is given off by the absorbent. To change automatically a thermostat 51 is provided to control by the connecting means 55 and the valve 54 the flow of water through the coils in the absorber and condenser. When the temperature of a space to be conditioned exceeds a predeter- I mined value, the flow of cooling water is in- 30 are such that liquid flows under the difference in pressure in the upper section of the vessel 21 and the lower section thereof from the latter intothe former. The pipe 20 with its contained pipe 2i serves as an hydraulic loop to compensate automatically for any slight differences in pressure a which may exist above the amount necessary to separator l3 at a level below the entrance of the pipe l4. The pipe it continues on the in ide 0.!

creased; when the temperature of a space to be conditioned falls'below a certain value, the flow of cooling water is decreased.

When the flow of cooling water is decreased the temperature of the absorbent in the absorber rises above that temperature at which the absorbent can absorb water vapor and the cooling action in the apparatus is reversed. Water vapor rises from the absorbent in the spiral channel in r the absorber into the evaporator where it condenses on the finned coils therein thus serving to heat the secondary refrigerant. This secondary The heat supplied to said secondary f refrigerant may be either positive or negative; if

1, pressure than the other, the, high pressure part refrigerant then transfers the heat to the point of utilization thus heating the air or other fluid which it is desired to heat. After condensing on the coils in the evaporator the liquid flows down the spiral fins and through the drain pipe into the absorber. v I

Since the flow ofcooling water through the condenser is decreased, vapor which would other-' wise condense therein flows upward in the pipe 2| after breaking the liquid seal in said pipe and passes into the evaporator at the distributing device and is condensed on the finned coils thus adding more heat to the secondary refrigerant. This condensate also flows to the absorber by way of the drain pipe. During this latter opera- 5 tion the hydrostatic balance. set up by the various loops and relative levels of chambers is disturbed and steam flows through these loops. This temporary disturbance of function does not prevent the unit from heating and the seals reestablish o themselves automatically when water is turned on. While the cooling water is oil the flow of vapor from the lower chambers to the upper chambers is maintained since the pressure of the" entire system rises relatively and the lower chambers, i. e., the regenerator, the vapor separator and the condenser are still at a relatively higher pressure than the upper chambers, i. e., the evaporator and the absorber.

Other modes of applying the principle of this inventionmay be employed instead of those explained, provided those stated by any of the following claims or their equivalent is employed.

I therefore particularly point out and distinctiy claimwas my invention:

1. Vacuum absorption refrigeration apparatus including a unitary hermetically sealed vessel divided into two parts one of which is maintained at a higher pressure than the other, the high in pressure part containing a regenerator and a condenser and the low pressure part containing an evaporator and an absorber,;thermally operated means for transferring the absorbent from the absorber to the regenerator, said means in- -1 eluding an open unrestricted channel connecting the absorber and the regenerator, and means for allowing thermal communication between the hot absorbent and the cool absorbent.

2. Vacuum' absorption refrigerator comprising hermetically sealedapparatus' divided into two parts one of which is maintained at a higher containing a regenerator and a condenser and the low pressure part containing an evaporator and an absorber; means for transferring weakened absorbent from theabsorber to the regenerator including means for allowing thermal communication between the cool absorbent and hot absorbent, and means for separating the to boiling absorbent leaving the regenerator into vapor and liquid including a vapor separator and a tube extending from the regenerator into the lower portion of said vapor separator and directed tangentially toward the inside of said vapor 6 separator. q

3. Vacuum absorption refrigerator comprising hermetically sealed apparatus divided. into two 4 parts one of which is maintained at a higher pressure than the other, the low pressure part to containing an absorber and an evaporator and the high pressure part containing a regenerator and a condenser; means for separating boiling absorbent leaving the regenerator into liquid and vapor, said means comprising a vapor separator, 10

separator for transferring the boiling absorbent theretofrom the regenerator, and a second pipe concentric with said first pipe and surrounding the same for transferring vapor from the separator to the condenser.

4. Vacuum absorption refrigerator comprising and a condenser; means for separating boiling absorbent leaving the regenerator into liquid and vapor, said means comprising a vapor separator and means extending through the base thereof for transferring the boiling absorbent thereto from the regenerator, said last named means including a pipe which directs boiling absorbent tangentially against the side of said vapor separator.

5. Vacuum absorption refrigerator comprising hermetically sealed apparatus divided into two parts one of which is maintained at a higher pressure than the other, the low pressure part containing an absorber and an evaporator and the high pressure part containing a regenerator and a condenser; means for separating boiling absorbent leaving the regenerator into liquid and vapor, said means including a vapor separator and a pipe which extends through the base of the vapor separator and directs boiling absorbent tangentially against the inside of said vapor separatorpand means for removing-liquid collecting on the bottom of said vapor separator including a passage therefrom in thermal communication with absorbent-refrigerant mixture leaving the abs-sorber,v

6. Vacuum absorption refrigerator comprising hermetically sealed apparatus dividedinto two parts oneof which is maintained at a higher pressure than the other, the low pressure part containing an absorber and an evaporator and the high pressure part containing a regenerator and a condenser; means for separating boiling absorbent leaving theregenerator into liquid and vapor, said means including a vapor separator and means extending through the base thereof for transferring the boiling absorbent from the regenerator to the vapor separator; and means for removing the vaporized refrigerant collecting in the upper part of the vapor separator including a pipe, extending upwardly into said vapor separator to a point above the entrance point of the vapor-liquid mixture but at the middle of said vapor separator horizontally, said pipe extending downwardly into a condenser containing OOOHDB 00115.

- 7. Vacuum absorption refrigerator comprising hermetically sealed apparatus divided into two parts one of which is maintained at a higher pressure than the other. the low pressure part containing an absorber and an evaporator and the high pressure part containing a regenerator and a condenser; means for separating boiling upper part of the vapor separator including a pipe extending upwardly into said vapor separator to a point above the entrance point of the vaporliquid-mixture but at the middle of said vapor a 'pipe extending through the-base of the vapor I separator horizontally and extending downwardly into a condenser containing cooling coils; and an hydraulic loop in open communication between the condenser and the regenerator.

8. Vacuum absorption refrigerator comprisinghermetically sealed apparatus divided into two parts one of which is maintained at a higher pressure than the other, containing an absorber and an evaporator and the high pressure part containing a regenerator and a condenser; means for separating boiling absorbent leaving the regenerator into liquid and vapor, said means including a vapor separator and means extending through the base thereof for transferring the boiling absorbent from the regenerator to the vapor separator; means for removing the vaporized refrigerant collecting in the upper part of the vapor separator including a. pipe extending upwardly into said vapor separator to a point above the entrance point of the vapor-liquid mixture but at the middle of said vapor separator horizontally and extending downwardly into a condenser containing cooling coils;

and an hydraulic loop in open communication between the condenser and the regenerator, said loop including a pipe passing from the condenser to the evaporator.

9. Vacuum absorption refrigerator comprising.

- a pipe extending upwardly into said vapor separator above the entrance point of the vaporliquid mixture but at the middle of said vapor separator horizontally and extending downwardly into a condenser containing cooling coils; and a pipe leaving the side of the vapor separator at a point above the entrance of the regenerated absorbent and passing into the regenerator.

10. Vacuum absorption refrigeration apparatus including an absorber, a regenerator, a condenser and an evaporator which latter comprises vertical tubes containing secondary refrigerant, said tubes being formed with' helically wound fins thereon, and means for introducing primary re,- frigerant at the top of the helix defined by the fins,

1 Vacuum absorption refrigeration apparatus including an absorber, a regenerator, a condenser and an evaporator which latter comprises vertical tubes containing secondary refrigerant, said tubes being formed with helically wound fins thereon, means for introducing primary refrig erant at the top of the helix defined by the fins and said evaporator containing an approximately V-shaped shield so-posltioned in the evaporator that the upper portion of said shield is substantially above the highest point in the evaporator where refrigerant is evaporated and the lower portion of said shield is substantially above the lowest point at which refrigerant is evaporated.

but below said highest point.

12. Vacuum absorption refrigeration apparatus the low pressure party ing a refrigerant onto the helical fins, said fins being so-spaced that the liquid is retained by surface tension within the passage defined thereby cluring its downward traverse thereof.

13. Vacuum absorption refrigeration apparatus including a regenerator, a condenser and a vapor separator; a passage between said regenerator and said vapor separator; and a second passage between said condenser and said vapor separator, said first passage being in thermal communication with said second passage outside the vapor separator.

l4. Vacuum absorption apparatus comprising an hermetically sealed vessel divided into two parts one of which is maintained at a, higher pressure than the other, a regenerator, transfer means for fluid between the regenerator and a vapor separator, said means comprising a pipe projecting from said regenerator into and in open communication with said vapor separator and so-positioned that fluid passing into said vapor separator is projected tangentially against the inside thereof, an overflow" pipe between said vapor separator and said regenerator, communicating means in thermal communication with the regenerator-vapor separator transfer means between said vapor separator and a condenser, means for transferring condensate from said condenser into an evacuated evaporator comprising a liquid seal, an hydraulic loop between said regenerator and said condenser, means for transferring liquid from said vapor separator to an absorber comprising thermal communication means between said liquidand an absorbent-refrigerant mixture having a lower temperature relative thereto, thermal communication means in said evaporator between evaporating refrigerant and a secondary refrigerant, means for utilizing the thus-produced heat absorbent qualities of said, secondary refrigerant, means for transferring refrigeration from said evaporator into an absorber, a cooling coil in said absorber, absorbent-refrigerant contact means in said absorber, and absorbent-refrigerant mixture transfer means between said absorber and said regenerator comprising thermal communication means between said mixture and liquid being transferred from said vapor separator to said absorber.

15. Vacuum absorption apparatus comprising a, regenerator, transfer means for fluid between the regenerator and a vapor separator, said I means comprising a pipe projecting from said regenerator into and in open communication with said vapor separator and so-positioned that fluid passing into said vapor separator is projected including an evaporator having vertical tubes,

wound with helical flns, and means for introductangentially against the inside thereof, an overflow pipe between said vapor separator and said regenerator, communicating means in thermal communication with the regenerator-vapor separator transfer' means between said vapor separator and a condenser, means for transferring condensate from said condenser into an evacuated evaporatorcomprising a liquid seal, an hydraulic loop between said regenerator and. said condenser, means for transferring liquid. from said vapor separator to an absorber comprising thermal communication means between said liquid and an absorbent-refrigerant mixture having a lower temperature relative thereto, thermal communication means in said evaporator between evaporating refrigerant and a secondary refrigerant, means for utilizing the thus-produced heat absorbent qualities of said secondary refrigerant, means for transferring refrigerant from said evaporator into an absorber, a cooling coil in said absorber, absorbent-refrigerant contact means in said absorber, and absorbent-refrigerant mixture transfer means between said absorber and said regenerator comprising thermal communication means between said mixture and liquid being transferred from said vapor separator to said absorber.

16. Vacuum absorption apparatus comprising an evaporator, an absorber situated below said evaporator, a heat exchanger, a condenser situated below said absorber, a regenerator situated below said condenser, heating means for the regenerator, cooling means for the absorber and the condensenfluid transfer means between the regenerator and the condenser comprising a vathe condenser, fluid transfer means between the condenser and the evaporator comprising an hydraulic loop, fluid transfer means between the condenser and the regenerator comprising an hydraulic loop, fluid transfer means between the vapor separator and the absorber, fluid transfer means between the absorber and the regenerator, means for thermal communication between fluids passing from the vapor separator to the absorber and fluids'passing from the absorber to the regenerator, and fluid transfer means between the evaporator and the absorber.

1'7. In a vacuum absorption refrigeration apparatus wherein the absorbent is reconcentrated by boiling means, means for separating liquid and vapor including a! vapor separator of circular cross-section, a tube directed to convey a mixture of vapor and liquid from the boiling means into the separator and to inject the said mixture against the inside wall of the separator, and a second tube adapted to withdraw separated vapor from the separator at a point above the point of injection of the aforesaid mixture, said second tube being concentric with and in part surrounding said first tube.

18. In a vacuum absorption refrigerator, in

combination with a regenerator, condenser and absorber, a spirally wound heat exchanger for exchanging heat between weakened absorbent entering and concentrated absorbent leaving the regenerator, a vapor separator disposed above the heat exchanger, and two concentric pipes passing through the center of the heat exchanger,

the inner of said pipes being adapted to convey a mixture of liquid and vapor from the regenerator to the vapor separator, and the outer of said pipes being adapted to withdraw separated vapor from the separator at a point above the point of injection of the liquid-vapor mixture and to convey the same to the condenser.

19. A vacuum absorption apparatus comprising a unitary hermetically sealed vessel divided into two parts one of ,which is maintained at a higher pressure than the other, the high pressure part containing a regenerator and a condenser and the low pressure part containing an evaporator and an absorber, means for separating the boiling absorbent leaving the regenerator into vapor and liquid including a vapor separator, means for transferring absorbent from the regenerator to the absorber by vapor lift action, means for transferring weakened absorbent from the absorber to the regenerator including an open unrestricted channel and means for allowing thermal contact between cool absorbent and the hot absorbent leaving the vapor separator.

20. Vacuum absorption refrigeration apparatus FRANCIS R. BICHOWSKY, 

